U.S. patent application number 14/022209 was filed with the patent office on 2014-05-29 for arrangement for securing elongated solar cells.
This patent application is currently assigned to Solyndra LLC. The applicant listed for this patent is Solyndra LLC. Invention is credited to Benyamin Buller, Brian H. Cumpston, Tim Leong.
Application Number | 20140144489 14/022209 |
Document ID | / |
Family ID | 39368030 |
Filed Date | 2014-05-29 |
United States Patent
Application |
20140144489 |
Kind Code |
A1 |
Buller; Benyamin ; et
al. |
May 29, 2014 |
Arrangement for Securing Elongated Solar Cells
Abstract
A solar panel apparatus includes a set of photovoltaic modules.
The modules are configured to photovoltaically generate electricity
from light. Each module is elongated along an axis and has first
and second axially opposite ends. An end rail has a groove into
which the first end of each module is potted in place with potting
material.
Inventors: |
Buller; Benyamin;
(Cupertino, CA) ; Cumpston; Brian H.; (Pleasanton,
CA) ; Leong; Tim; (Danville, CA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Solyndra LLC |
Fremont |
CA |
US |
|
|
Assignee: |
Solyndra LLC
Fremont
CA
|
Family ID: |
39368030 |
Appl. No.: |
14/022209 |
Filed: |
September 9, 2013 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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11934267 |
Nov 2, 2007 |
8530737 |
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14022209 |
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60859188 |
Nov 15, 2006 |
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60859033 |
Nov 15, 2006 |
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60859212 |
Nov 15, 2006 |
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60859213 |
Nov 15, 2006 |
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60859215 |
Nov 15, 2006 |
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60861162 |
Nov 27, 2006 |
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60901517 |
Feb 14, 2007 |
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Current U.S.
Class: |
136/251 |
Current CPC
Class: |
Y02E 10/50 20130101;
H02S 30/10 20141201; H02S 20/00 20130101 |
Class at
Publication: |
136/251 |
International
Class: |
H01L 31/042 20060101
H01L031/042 |
Claims
1. A solar panel apparatus comprising: a set of photovoltaic
modules configured to photovoltaically generate electricity from
light, each module elongated along an axis and having first and
second axially opposite ends; and an end rail having a groove into
which the first end of each module is potted in place with potting
material, said groove being bounded by two opposing side surfaces
and a bottom surface extending from one of the side surfaces to the
other, and wherein the end rail and the potting material are
separate components, wherein a flexible sheath is inserted in the
end rail such that the potting material is disposed between the two
opposing side surfaces of the groove and the flexible sheath, and
wherein the set of photovoltaic modules are
electrically-interconnected by an electrical line that is covered
by the potting material.
2. The apparatus of claim 1 wherein the groove is elongated along
the length of the rail.
3. The apparatus of claim 1 wherein the potting material forms a
seal about each module fully about the circumference of the
module.
4. The apparatus of claim 3 wherein the seal is hermetic.
5. The apparatus of claim 1 further comprising a socket in the
groove, covered by the potting material and fixing the position of
the first end of the at least one module in the end rail.
6. The apparatus of claim 1 further comprising sockets that are in
the groove, covered by the potting material and spaced apart along
the length of the first rail, each socket fixing the position of
the first end of a respective one of the modules.
7. The apparatus of claim 6 wherein the sockets are parts of a
socket strip that is seated in the groove and covered by the
potting material.
8. The apparatus of claim 1 further comprising an electrical socket
contact that is in the groove and contacting an output contact of a
respective module to conduct electricity from the module.
9. The apparatus of claim 8 wherein the potting material engages
the socket contact.
10. The apparatus of claim 8 wherein the potting material surrounds
an interface between the socket contact and the output contact.
11. The apparatus of claim 1 wherein the potting material is
electrically insulating.
12. (canceled)
13. The apparatus of claim 1 further comprising a second end rail
with a second groove, wherein potting material in the second groove
fixes the second ends of the modules in the second groove.
14. The apparatus of claim 1 wherein the modules are in a
one-dimensional array.
15. The apparatus of claim 1 wherein the modules are in a
two-dimensional array.
16. The apparatus of claim 1 wherein the modules are fixed in a
mutually parallel configuration.
17. The apparatus of claim 1 wherein each module is configured to
photovoltaically generate electricity from light directed toward
the module from any radially-inward direction.
18-25. (canceled)
26. The apparatus of claim 1, wherein the groove has an opening
opposite the bottom surface, the modules' axes extend through both
the groove opening and the bottom surface, and the modules have
output contacts located between the side surfaces.
27. The apparatus of claim 1, wherein a stiffening bar is secured
to the bottom surface of the groove.
28. The apparatus of claim 27, wherein the stiffening bar contacts
the two opposing side surfaces.
29. The apparatus of claim 10, wherein the interface are outside
the flexible sheath.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application is a continuation of U.S. patent
application Ser. No. 11/934,267 filed Nov. 2, 2007, now U.S. Pat.
No. ______ which claims the benefit of U.S. Provisional Application
Nos. 60/859,033; 60/859,188; 60/859,212; 60/859,213; and
60/859,215, all filed Nov. 15, 2006, U.S. Provisional Application
No. 60/861,162 filed Nov. 27, 2006 and U.S. Provisional Application
No. 60/901,517, filed Feb. 14, 2007, all hereby incorporated by
reference in their entirety.
TECHNICAL FIELD
[0002] This application relates to solar panels.
BACKGROUND
[0003] A solar panel includes an array of photovoltaic modules that
are electrically connected to output terminals. The modules output
electricity through the terminals when exposed to sunlight.
BRIEF DESCRIPTION OF THE DRAWINGS
[0004] FIG. 1 is a perspective view of a solar panel, including a
one-dimensional array of photovoltaic elongated photovoltaic
modules mounted in a frame.
[0005] FIG. 2 is an exploded view of the panel.
[0006] FIG. 3A is a sectional view of an exemplary one of the
modules.
[0007] FIG. 3B is a sectional view taken at line 3B-3B of FIG.
3A.
[0008] FIG. 4 is a perspective view of a rail of the frame.
[0009] FIG. 5 is a sectional view showing interconnecting parts of
the module and the rail.
[0010] FIG. 6 is a top view of the array, showing electrical lines
connecting the modules in parallel.
[0011] FIG. 7 is a side sectional view of the array, showing the
spatial relationship of the modules to each other and to a
reflective backplate.
[0012] FIG. 8 is a sectional view similar to FIG. 7, showing the
array exposed to sunlight.
[0013] FIG. 9 is a sectional view similar to FIG. 5, with an
alternative configuration of the interconnecting parts of the
module and the rail.
[0014] FIG. 10 is a sectional view similar to FIGS. 5 and 9,
showing another alternative configuration of the interconnecting
parts of the module and the rail.
[0015] FIG. 11 is a top view similar to FIG. 6, showing electrical
lines connecting the modules in series.
[0016] FIGS. 12-14 are perspective views of alternative
modules.
[0017] FIG. 15 is a sectional view of a two-dimensional array of
the modules.
DESCRIPTION
First Embodiment
[0018] The apparatus shown in FIGS. 1-2 has parts that are examples
of the elements recited in the claims. These examples enable a
person of ordinary skill in the art to make and use the invention
and include best mode without imposing limitations not recited in
the claims. Features from different embodiments described below can
be combined together into one embodiment in practicing the
invention without departing from the scope of the claims.
[0019] The apparatus is a solar panel 1. It includes a
one-dimensional array 5 of parallel elongated photovoltaic modules
10. The modules are secured in a frame 12 with potting material 110
(FIG. 5). The frame 12 has a front opening 13 configured to receive
sunlight. The photovoltaic modules 10 output electricity through
two outlet terminals 16 and 17 when exposed to light.
[0020] The modules 10 can be identical. As exemplified by a module
10 shown in FIGS. 3A-3B, each module 10 can include a core 20
centered on an axis A. The core 20 can be surrounded by a
photovoltaic cell 22 extending fully about the axis A. The cell 22
can itself be surrounded by a transparent protective tube 24 capped
by two axially opposite caps 26. The photocell 22 typically has
three layers--a radially inner conductive layer 31 overlying the
core 20, a middle semiconductor photovoltaic layer 32, and a
transparent conductive radially outer layer 33. The inner and outer
layers 31 and 33 are typically connected to an anode output contact
41 and a cathode output contact 42 at the axially opposite ends 51
and 52 of the cell 22.
[0021] As shown in FIGS. 3A-3B, the photovoltaic middle layer 32
has a photovoltaic surface 54 that receives light to
photovoltaically generate electricity. The electricity is conducted
through the conductive layers 31, 33 to be output through the
contacts 41, 42. The photovoltaic surface 54 in this example is
cylindrically tubular. It thus includes an infinite number of
contiguous surface portions 55, each facing away from the axis A in
a different direction. These include, with reference to FIG. 3B,
the four orthogonal directions up, down, left and right. Therefore,
the cell 32 in this example, and thus the module 10, can
photovoltaically generate electricity from light (exemplified by
arrows 57) directed toward the module 10 from any radially-inward
(i.e., toward the axis A) direction.
[0022] The length L.sub.s of the photovoltaic surface 54 is greater
than, and preferably over five times or over twenty times greater
than, the diameter D.sub.s of the photovoltaic surface 54.
Similarly, the length L.sub.m of the module 10 is greater than, and
preferably over five times or over twenty times greater than, the
diameter D.sub.m of the diameter of the module 10. The module's
length and diameter in this example correspond to the lengths and
diameter's of the module's outer tube 26.
[0023] As shown in FIG. 1, the frame 12 is a securing structure
that includes two axially-extending side rails 70 and
laterally-extending first and second end rails 71 and 72. In this
example, the rails 70, 71 and 72 are held together by corner
brackets 74. The end rails 71, 72 rigidly secure the modules 10 in
place and are themselves rigidly secured together by the side rails
70.
[0024] The rails 70, 71, 72 can be extruded and stocked in long
lengths from which shorter lengths can be cut to match the
individual length needed for each application. To simplify
warehousing and manufacturing, the side rails 70 can be cut from
the same stock material as the end rails 71, 72.
[0025] The rails 70, 71, 72 can be formed of fiber reinforced
plastic, such as with pultruded fibers 75 extending along the full
length of the rail as illustrated by the first end rail 71 in FIG.
4. The fibers 75 resist stretching of the rail 71 to help maintain
the preset center spacing of the modules 10 while enabling flexing
of the respective rail. Examples of pultruded fibers are glass
fibers and organic fibers such as aramid and carbon fibers, and
compound materials.
[0026] The end rails 71, 72 in this example are identical, and
described with reference to the first end rail 71 in FIG. 4. The
end rail 71 has a laterally extending groove 80. A stiffening bar
81 can be adhered to the bottom surface of the groove 80 to stiffen
the rail 71. The bar 81 in this example is narrower than the groove
80.
[0027] A socket strip 82 in the groove 80 can be adhered to both
the top of the bar 81 and the bottom of the groove 80. The socket
strip 82 in this example contains a chain of metal socket contacts
84 interconnected by an electrical bus line 90, all overmolded by a
rubber sheath 92. The sheath 92 can electrically insulate the bus
line 90 and secure the socket contacts 84 in place at a
predetermined center spacing. The rail 71 accordingly contains the
strip 82, and thus also the sockets 84 and electrical lines 90 of
the strip 82. The width W.sub.s of the strip 82 can approximately
equal the width W.sub.g of the groove 80 so as to fit snugly in the
groove 80.
[0028] The sheath 92 can be flexible, and even rubbery, to reduce
stress in the modules 10 and facilitate manipulation when being
connected to the modules 10 or inserted into the rail 71. If
sufficiently flexible, the sheath 92 can be manufactured in long
lengths and stocked in a roll. Shorter lengths can be cut from the
roll as needed, to match the length and number of sockets 84 needed
for each application. Even if made flexible, the sheath 92 is
preferably substantially incompressible and inextensible to
maintain the center spacing of the modules 10. The sheath 92 can
alternatively be rigid to enhance rigidity of the rail 71 or have
rigid and flexible portions.
[0029] As illustrated with reference to one end 51 of one module 10
shown in FIG. 5, each electrical contact 41, 42 of each module 10
can be both electrically coupled to and mechanically secured by a
corresponding socket contact 84. Potting material 110 can fill the
groove 80 to encase the contacts 41, 84 and form a seal with each
module 10 fully about the module 10. This can isolate and
hermetically seal the socket contacts 84 and module contacts 41, 42
from environmental air, moisture and debris, and further isolate
any electrical connection between the device and the frame. The
potting material 110 further adheres to each module 10 to secure
the module 10 in place and stiffens the orientation of the ends 51,
52 of each module 10. Bowing of the module 10 from gravity and
vibration is less than it would be if its ends 51, 52 were free to
pivot about the socket 84. The reduction in bowing reduces the
chance of the modules 10 breaking or contacting each other and
helps maintain the predetermined center spacing of the modules
10.
[0030] As shown in FIG. 6, the electrical line 90 in the first end
rail 71 connects all the module anodes 41 to the common anode
terminal 16. The electrical line 90 in the second end rail 72
connects all the module cathodes 42 to the common cathode terminal
17. The modules 10 are thus connected in parallel.
[0031] The frame 12 can be mounted in front of a reflective
backplate 14. The backplate 14 has a reflective surface such as a
mirror surface or white coating, and is preferably parallel with
the module axes A.
[0032] In the assembled panel 1 shown in FIG. 7, the center spacing
S.sub.1 between modules 10 equals the diameter D.sub.s of the
photovoltaic surface 54 plus the spacing S.sub.2 between adjacent
photovoltaic surfaces 54. The spacing S.sub.2 is about 0.5 to about
2 times the diameter D.sub.s. The spacing S.sub.3 between each
photovoltaic surface 54 and the reflective surface 14 is preferably
about 0.5 to about 2 times the diameter D.sub.s.
[0033] FIG. 8 shows the panel 1 exposed to sunlight 130. As shown,
the light 130 can strike each photocell 22 in multiple ways. Light
passing through the array 5, between photocells 22, is reflected by
the reflective surface 14 back toward the array 5 to strike one of
the photocells 22. The light can also reflect off one cell 22 to
strike a neighboring cell 22.
Potting and Encapsulation Material
[0034] Encapsulants and potting compounds are resins or adhesives
that are used to encapsulate circuit boards and semiconductors,
fill containers of electronic components, and infiltrate electrical
coils. They provide environmental protection, electrical insulation
and other specialized characteristics. In most embodiments in
accordance with the present application, encapsulants and potting
materials are used as adhesive, insulation, bonding agents,
encapsulating coating, sealant or gap filling agent to enhance the
mechanical integrity of the final solar cell assembly. Encapsulants
and potting compounds belong to a broader category of electrical
resins and electronic compounds that includes adhesives, greases,
gels, pads, stock shapes, gaskets, tapes, and thermal interface
materials. Most potting compounds are based on polymeric resins or
adhesives; however, materials based on ceramic or inorganic cements
are often used in high temperature applications. Some encapsulants
and potting compounds are designed to form a thermally conductive
layer between components or within a finished product. For example,
these thermally conductive products are used between a
heat-generating electrical device and a heat sink to improve heat
dissipation.
[0035] Important specifications for encapsulants and potting
compounds include electrical, thermal, mechanical, processing, and
physical properties. Electrical properties include electrical
resistivity, dielectric strength, and dielectric constant or
relative permittivity. Thermal properties include service
temperature, thermal conductivity, and coefficient of thermal
expansion (CTE). Mechanical properties include flexural strength,
tensile strength, and elongation. Processing and physical
properties include viscosity, process or curing temperature,
process or cure time, and pot life. Encapsulants and potting
compounds vary in terms of features. Many products that are
designed for electrical and electronics applications provide
protection against electrostatic discharge (ESD), electromagnetic
interference (EMI), and radio frequency interference (RFI).
Materials that are electrically conductive, resistive, insulating,
or suitable for high voltage applications are also available. Flame
retardant products reduce the spread of flames or resist ignition
when exposed to high temperatures. Thermal compounds and thermal
interface materials that use a phase change are able to absorb more
heat from electronic devices or electrical components. In some
embodiments, it is necessary to select encapsulants and potting
compounds for solar cell assembly based on the geographic location
where the solar cell assembly is to be installed. In some
embodiments, encapsulants and potting compounds are selected based
on multiple factors such as temperature, rainfall level and
snowfall level of the location.
[0036] In some embodiments, common potting compounds and casting
resins are used to fill, for example, the grooves 80 of the end
rails 71 and 72. Potting material is use to secure members of a
given solar cell assembly, for example, to secure the stiffening
bar 81 to the bottom or sides of the grooves 80, or to the inner or
outer surface of the end rail 71 or 72. In some embodiments,
encapsulants are used to seal or cover electrical connections. In
typical embodiments, encapsulant layers are less than 10
millimeters thick. In some embodiments, gap filling or underfill
compounds are used to fill in gaps or spaces between two surfaces
to be bonded or sealed, for example, the stiffening bar 81 to the
bottom or sides of the grooves 80, or to the inner or outer surface
of the end rail 71 or 72. Encapsulants and potting compounds are
based on a variety of chemical systems. Examples of potting and
encapsulant materials include but are not limited to, for example,
Acrylic/Polyacrylate (excellent environmental resistance and
fast-setting times compared to other resin systems), Bitumen/Coal
Tar (water resistance and low cost), Bismaleimide (BMI) (high
temperature resistance), Cellulosic/Cellulose, Ceramic/Inorganic
Cement, Epoxy (high strength and low shrinkage during curing,
toughness and resistance to chemical and environmental damage),
Fluoropolymer (e.g., PTFE/PVDF for superior chemical resistance and
low friction), Isoprene/Polyisoprene, Liquid Crystal Polymer (LCP,
high strength and temperature resistance), Phenolics/Formaldehyde
Resins (e.g., Melamine, Furan, etc., thermosetting molding
compounds and adhesives that offer strong bonds and good resistance
to high temperatures and corrosion), Polyamide (e.g., Nylon as one
example of strong hot-melt adhesives), Polyamide-imide (PAI)
(excellent mechanical properties), Polybutadiene (e.g., for
dielectric potting compounds and coatings), Polycarbonate (PC)
(amorphous with excellent impact strength, clarity, mechanical and
optical properties), Polyethylene (PE), PET/PBT (Thermoplastic
Polyester), Polyester/Vinyl Ester, Polyolefin, Polypropylene (PP),
Polypropylene (PP) (hot-melt adhesive systems), Polysulphide,
Polyurethane (PU, PUR), Silicone, Styrene/Polystyrene, and Vinyl
(e.g., PVC/PVA/PVDC).
[0037] In some embodiments, polymers or resins used as potting and
encapsulant materials may be cured using various technologies that
include thermoplastic/hot melt methods, thermosetting methods
(e.g., cross-linking/vulcanizing), room temperature based methods
(e.g., curing/vulcanizing), UV/radiation based methods, and
reactive/moisture based methods. Polymers or resins used as potting
and encapsulant materials may also be cured in a single component
system, a two component system or even a multi-component
system.
[0038] Companies specialized in polymers or resins used as potting
and encapsulant materials and associated technologies include but
are not limited to DYMAX Corporation (Torrington, Conn.), GC
Electronics (Rockford, Ill.), Gelest, Inc. (Morrisville, Pa.), GS
Polymers, Inc. (Brea, Calif.), Henkel Corporation-Electronics
(Irvine, Calif.), Hernon Manufacturing, Inc. (Sanford, Fla.), ITW
Polymer Technologies-Insulcast Division (Montgomery, Pa.), Master
Bond, Inc. (Hackensack, N.J.), National Starch and Chemical Co.
(Bridgewater, N.J.) and Sauereisen, Inc. (Pittsburgh, Pa.).
Method of Assembly
[0039] Referring to FIG. 2, one method of assembling the panel 10
includes the following sequence of steps. First, the stiffening
bars 81 and socket strips 82 are secured in the grooves 80 of the
respective rails 71, 72. Then, the anode contacts 41 (FIG. 3A) of
the modules 10 are connected to the socket strip 82 in the first
end rail 71, and the cathode contacts 42 of the modules 10 are
connected to the socket strip 82 in the second end rail 72. The
side rails 70 are connected to the end rails 71, 72 with the four
corner brackets 74. In a potting step, the potting material 110
(FIG. 5) is flowed into each groove 80, to encase the respective
socket strip 82, and then hardened. The reflective surface 14 is
fixed to the back of the framed 12. The output terminals 16, 17 can
then be connected to an electrical device to power the device when
the modules 10 are exposed to light.
[0040] In an alternative method, the socket strips 82 are connected
to the modules 10 before being mounted in the grooves 80, so that
the socket strips 82 are more easily manipulated when connecting to
the modules 10.
Alternative Embodiments
[0041] In the figures cited below, parts labeled with primed and
multiply-primed reference numerals correspond to parts labeled with
equivalent unprimed numerals.
[0042] In the first embodiment, as shown in FIG. 5, the module
contact 41 is portrayed as cylindrical and grasped by the socket
contact 84. Alternatively, module contacts can have another shape
and need not be grasped by the socket contact 84. For example, FIG.
9 shows a spherical module contact 41' and an alternative socket
strip 82' in which the sheath 92', instead of the socket 84, grasps
the module contact 41'. The material surrounding the hole in the
sheath 92', instead of the contact 84', thus serves as the socket
in this embodiment to secure the module 10 to the rail 71'.
Additionally, in contrast to FIG. 5, the stiffening bar 81' in FIG.
9 is as wide as the groove 80' to provide a snug fit, and the
socket strip 84' is narrower than the groove 80'. This enables the
potting material 110' to engage the stiffening module 81' and both
sides of the socket strip 82'.
[0043] FIG. 10 shows another alternative socket strip 82'. This
differs from the configurations of FIGS. 5 and 9 in the following
ways: The strip 82' of FIG. 10 neither receives nor secures the
module contact 41'. The modules 10 are thus secured to the rail 71
only by the potting material 110. The contacts 41', 84' of both the
module 10' and the strip 82' are outside the sheath 92'. The
potting material engages both contacts 41', 84', surrounds the
interface (point of contact) between the contacts 41', 84', and
reaches the peripheral edge of the interface.
[0044] In the first embodiment, as shown in FIG. 6, the modules 10
are electrically connected in parallel. In another embodiment shown
in FIG. 11, the modules 10 are connected in series. This can be
achieved by flipping the axial orientation of every other module 10
in the array 5. Each anode contact 41 can then be electrically
connected by an electrical line 90' to an adjacent cathode cell
22.
[0045] Although the photovoltaic surface 54 is preferably
cylindrical as shown above, other shapes are possible as mentioned
above. For example, FIG. 12 shows a module 10' (with its electrode
contacts omitted for clarity) that has a tubular photocell 22'
having conductive inner and outer layers 31' and 33' and a
photovoltaic middle layer 32'. The middle layer 32' is tubular with
a rectangular cross-section. It thus provides four contiguous
orthogonal flat photovoltaic surface portions 55' that face away
from the axis A in different directions and together extend fully
about the axis A. Like the cylindrical photocell configuration
described above, this rectangular configuration can
photovoltaically generate electricity from light rays directed
toward the module 10' from any radially-inward direction, even
though not all such light rays could strike the respective surface
portion 55' perpendicularly. Similarly, other choices of shape can
be used for the outer protective sleeves that fit over the cells
22.
[0046] Each module 10 in the above example includes a single
photovoltaic cell 22. Alternatively, each module 10 can have
multiple cells. For example, FIG. 13 shows a module 10'' having
three separate cells 22'' that together provide three separate
orthogonal photovoltaic surface portions 55'' that face away from
the axis A in three different directions. FIG. 14 shows a module
10''' made of two photocells 22''' glued back-to-back to provide
two separate flat photovoltaic surfaces 55''' facing away from each
other and the axis A.
[0047] The module 10 can have one contiguous photovoltaic cell, or
several photovoltaic cells connected in serial or in parallel.
These cells can be made as a monolithic structure that has the
plurality of cells scribed into the photovoltaic material during
the semiconductor manufacturing stage, as exemplified in U.S.
patent application Ser. No. 11/378835, which is hereby incorporated
by reference herein. Further, as noted above, the cross-sectional
geometry of such an elongated module need not be limited to the
cylindrical embodiment described above. For example, the module
cross-section can by polygonal, with a regular or irregular closed
shape.
[0048] In the first embodiment, each photocell 22 is sealed in a
transparent protective tube 24 (FIG. 3A). Alternatively, the tube
24 can be replaced with a protective coating or omitted entirely.
The potting material 110 could then form a seal with the coating or
with the photocell 22 itself.
[0049] In the first embodiment, the rail 71 has an single elongated
indentation 80 that receives all of the modules 10. Alternatively,
the rail 71 can have multiple bore-shaped indentations, not
necessarily elongated, each groove containing one socket to
mechanically secure and/or electrically one module.
[0050] FIG. 15 shows a two-dimensional array formed from three
one-dimensional arrays 5, 5', 5'' stacked one over the other. This
can be achieved by stacking three panels like the panel 1 (FIG. 1)
described above. Or by fitting three socket strips 82 side-by-side
in a common wide groove 80 and filling the groove 80 with the
potting material 110. The reflective surface 14 is mounted behind
the bottom array 5. A light ray 130' can be reflected any number of
times from any number of photovoltaic surfaces 54 of the three
arrays 5, 5', 5'' and from the reflective surface 14. The increased
number of cell surfaces 54 being exposed to the light ray 130'
increases efficiency of converting that light ray 130' to
electricity.
[0051] The apparatus 1 described above thus provides examples of
the following features: In a set of photovoltaic modules, the
modules are configured to photovoltaically generate electricity
from light. Each module is elongated along an axis and has first
and second axially opposite ends. An end rail has a groove into
which the first end of each module is potted in place with potting
material.
[0052] Preferably, the potting material forms a seal about each
module fully about the circumference of the module. The seal is
hermetic. A socket in the groove is covered by the potting material
and fixes the position of the first end of the first module in the
end rail.
[0053] Preferably, sockets in the groove are covered by the potting
material and spaced apart along the length of the first rail. Each
socket fixes the position of the first end of a respective one of
the modules. The sockets are parts of a socket strip that is seated
in the groove and covered by the potting material. Each electrical
socket contact in the groove is covered by the potting material and
contacts an output contact of a respective module to conduct
electricity from the module. The potting material engages the
socket contact. The potting material surrounds an interface between
the socket contact and the output contact.
[0054] In this example, the potting material is electrically
insulating. The modules are electrically-interconnected by an
electrical line that is covered by the potting material. A second
end rail has a second groove, and potting material in the second
groove fixes the second ends of the modules in the second groove.
The modules of the set can be in a one-dimensional array or in a
two-dimensional array. The modules are fixed in a mutually parallel
configuration. Each module is configured to photovoltaically
generate electricity from light directed toward the module from any
radially-inward direction.
[0055] In this example, a photovoltaic module is elongated along an
axis and has first and second axially opposite ends. The module is
configured to photovoltaically generate electricity from light
directed toward the module from any radially-inward direction. A
securing structure has an indentation into which the first end of
the module is potted in place with potting material.
[0056] The scope of the invention is defined by the claims, and may
include other examples that occur to those skilled in the art. Such
other examples are intended to be within the scope of the claims if
they have elements that do not differ from the literal language of
the claims, or if they include equivalent structural elements with
insubstantial differences from the literal language of the
claims.
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